21212010001 has 32 divisors (see below), whose sum is σ = 27753465600. Its totient is φ = 15742252800.

The previous prime is 21212009993. The next prime is 21212010011. The reversal of 21212010001 is 10001021212.

It is a cyclic number.

It is not a de Polignac number, because 21212010001 - 2³ = 21212009993 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21212010001.

It is not an unprimeable number, because it can be changed into a prime (21212010011) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 113895 + ... + 235363.

It is an arithmetic number, because the mean of its divisors is an integer number (867295800).

Almost surely, 2^21212010001 is an apocalyptic number.

It is an amenable number.

21212010001 is a deficient number, since it is larger than the sum of its proper divisors (6541455599).

21212010001 is a wasteful number, since it uses less digits than its factorization.

21212010001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121609.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21212010001 its reverse (10001021212), we get a palindrome (31213031213).

The spelling of 21212010001 in words is "twenty-one billion, two hundred twelve million, ten thousand, one".